Sea licehas become such a big problem that it is disruptingsalmonfarms around the world, and scientists have to work double time to mitigate, if not eliminate, infestation.

The tiny crustaceans continue to doggedly infest salmon farms in the US, Canada, Scotland, Norway and Chile, which are the major suppliers of the high-protein fish, Associated Press reports.

Apparently, scientists did not anticipate how big the sea lice problem affecting salmon farms would become. "Our work has to be quicker than the evolution of the lice", Jake Elliott, vice president of Cooke Aquaculture in Blacks Harbour, New Brunswick, Canada, was quoted as saying.

In August last year at a salmon science symposium organised by the UK's University of Stirling Institute of Aquaculture, scientist Armin Sturm disclosed that it had been 15 years since the last new anti-sea lice product was introduced. "We really should try to get some new drugs", he said then.

AP cited experts who say defeating the lice will take several new and established technology including older management tools such as pesticides, and newer strategies such as breeding for genetic resistance.

Underwater lasers

Innovative solutions in use or development include bathing the salmon in warm water to remove lice and zapping the lice with underwater lasers.

The pests, according to Fish Farmer Magazine, cost the global aquaculture industry about $1 billion annually.

Saying it is the biggest threat to their industry, salmon farmers say the sea lice is making the fish more expensive to consumers.

Shawn Robinson, a scientist with the Canadian Department of Fisheries and Oceans, said the only hope is to develop new methods to control the spread of lice, which are present in the wild, but thrive in the ocean pens for fish farming.

"There are not enough tools right now to allow the farmer to really effectively deal with it," Robinson told AP.